Measuring instrument



F. H. MARKWICZM MEASURING INSTRUMENT Filed Dec.

May 23, W39.

6, 1937 2 Sheets-Sheet l ATTORNEY may 23, 1939. F. H. MARKWICK MEASURINGINSTRUMENT Filed Dec. 6, 1937 2 Sheets-Sheet 2 5 INVENTOR JAM/imATTORNEY Patented May 23, 1939 UNITED STATES 2,159,335 msonme msramms'rFrederick H. Markwick, Dayton, Ohio, assignor to The Sheilield GageCorporation, Dayton, Ohio,

a corporation of Ohio Application December 6, 1937, Serial No. 178,289

column.

This invention relates to measuring or gauging devices and the like. I

7 One object of the invention is the provision of a gauging'device inwhich there is a gauging-memher adapted for cooperation with the work,the

device having an extension adapted to be inter- I posed between the workand the gauging member and capable of being readily moved from an oper-I ative to an inoperative position.

Another object of the invention is the provision of a'gauging device ofthe character mentioned including a gauging -member having 3. gaugingpoint adapted for cooperation with the work, an additional member beingprovided so 1 that it may be readily interposed between the gaugingpoint and the work and having a work contacting 'end which is flat sothat it may be used for measuring work pieces where the part it engagesis round or convex in form.

Another object of the invention'is the provision of an attachment for agauge having a gauging member provided with a gauging point, theattachment being of such character that-it may be readily connected to agauging instrument to 25 adapt the instrument for cooperation with awork specimen where .the engaged part of the work specimen is rounded atthe point of engagement. Other objects and advantages of the inventionwill be apparent from the following description,

0 the appended claims and the accompanying ing attachment; and

40 Fig. 4 is a vertical section taken on the line 4-4 of Fig. 3.Referring more particularly to the drawings by reference numerals, lldesignates a gauging or measuring instrument having a movable gauging 45member II which is adapted for axial movement from the base l6 having awork support l1. Vertical movements of the housing areeflected byrotating a hand wheel I! which is fixed toa shaft 2| on which is apinion 2| meshing with rack teeth 22 on the post IS. The shaft 20 isrotatably carried by the housing I. Suitable clamp means n operatedbyhand W e l 34 is provided tor holding the housing in the post.

As herein shown tor exemplary purposes, the work gauging member II is aplunger which is vertically slidable in a sleeve 21 having a fixedposition in the housing It. The lower end of the sleeve 21 rotatablysupports the holding member I! which is provided with a transverselyextending spring steel plate 28 having a rectangular hole in which thetapered portion 29 of the plunger rests. This tapered portion 28 of theplunger Ii is of rectangular cross-section and fits in the hole in theplate 28 so that when the holding member I! is rotated the plate 28,which is supported on the pointed end of an adjusting screw 28, moveswith it and rotates the plunger ll about its own axis. The upper end ofthe plunger has an inclined surface 30 engaging the lower end of avertically movable block 3| which is carried by flexible spring plates}!extending from a fixed block 33, the construction being such that theblock 3| may move vertically to swing an arm or pointer 34 which isconnected to the two blocks ii and 33 by means of two spaced flexiblespring blades 36. The position of the arm 34 is indicated on a scale I!by means of an optical system including a reflecting prism 38 in frontof the light source 38 which throws a visible indiany position ofadjustment on cation upon the scale 31 of the position of thepointer 3|,thus giving a reading on the scale in accordance with thesposition ofthe plunger II.

The plunger II has a rounded hard work contacting point 40 as shown inFig. 3 so as to be adapted for direct engagement with a work specimen inwhich the gauged surface is flat or horizontal, it being understood thatthe gauged specimen is placed on the work support I! and engaged by thelower end of the plunger II so that if the work specimen is larger orsmaller than a standard piece the diilerence in size will be indicatedby comparing the indications obtained on the scale when using thestandard piece and when checking the work specimen. I

Removably secured to the housing of the gauging device'is an attachment43 of such character as to adapt the gauging device to gauge or compareparts where the part engaged is a rounded surface, the gau ingattachment also providing an extension which may be conveniently movedto operative and inoperative positions so as to provide an extensionplunger in alignment with the plunger Ii and between the plunger ll anda work specimen placed on the work support IT.

The attachment 43 comprises a cast metal block J4 having threadedpassages 4Q so that it may be detachably supported on the lower wall 46of the housing ll by means of attaching screws 41. t It is preferablyarranged, as shown, in back of the holding member I: and in back of theplunger:

II where it will not interfere with 9. 83118 8 operation in which thepoint of the plunger II is brought into direct contact with the workspecimen. Movably'supported on the block 44, preferably by means of apivot pin 48, is an arm 49 which,in its normal operative position,extends downwardly and adjacent the plunger II and provides a mountingfor a movable work contactingmeans shown as a plunger 5llwhich projectsfrom the upper and lower surfaces 5i and 52 of the arm end. The plunger50 is guided for axial movements in guide sleeves 53 which are pressedin a passage 54 in the arm end. One side of the plunger has a recess 55cooperating with a pin 56 extending through and fixed in the end of thearm 49 so'as to limit the travel of the plunger 50 and prevent it fromfalling from the arm. Spring means 51 urges the plunger down- Vtransverse surface 59 adapted for engagement with the lower end of theplunger H. The lower end of the plunger 50 is also provided with atransversely extending flat work engaging surface 60 so that it may beconveniently used with '25 a work piece having a rounded or convexsurface.

It may be used, for example, in measuring or comparing screw threads. Athreaded work piece ii may. be placed on two round bars 52 with asingleround bar 63 positioned on top of 90 the work piece, the bars 62and 63 being of such size as to engage the thread sides at suitablepoints so that the diameter of the threads can be checked by comparingwith a standard threaded piece on which the same bars 62 and 63 areused,

95 or checked by setting with a master or distance block. With the lowerend of the plungertil having a flat transverse surface, it will beapparent that great care or accuracy in exactly centering the bar 63with respect to the axis 40 of the plunger 59 need not'be exercised.

The bar 49, when in its operative position, is

'- held rigidly in place so that the upper end of the plunger50yieldin'gly contacts the lower end of the plunger II, which is forcedupwardly a very 44 slight amount by the plunger 50 when the latter is inits lowermost position. The means for fixing the arm 49 securely inplace preferably comprises an adjustable knob 65 having a threadedportion 94 screwed into the block 44. The inner end of 50 the threadedportion 66 may be moved against a locating ball 51 so as to force-thesame into a notch 68 in the bar 49, so located that when the ball 91 isforced against it, the axis of the plunger "is in vertical alignmentwith the plunger H.

- 8| when the knob 55 is turned to release the pressure on the ball 51,the arm may be swung about its pivot pin 48. Opposite the ball 61 isafsecond ball 10, yieldingly held against the notch II in the arm bymeans of a spring '12 The pressure of the ball Il may be readilyovercome after the knob 05 is released, to permit swinging of the arm49. Arm 49 may thus be readily swung by the operator, after he releasesthe knob 65, and moved to the position indicated in dotted lines in Fig.3

preferably held in its inoperative position by yielding means on one orboth sides of the arm. As shown this yielding means comprises a ball 14urged yieldingly by spring 15 into a conical recess 16 provided in thearm. A screw 11 holds the spring 15 in place and applies suflicientpressure to the spring I5 so that the ball I6 holds the arm againstgravity, but permits the arm to be manually moved by the operator at anytime.

It will thus be seen that the attachment provides a simple means forincreasing the effective adaptations and use of a gauging instrument, asthe extension plunger 50 may be very readily. moved by the operator intooperative and inoperative positions. When moved to its operativeposition, with the housing l4 raised upon the supporting post l5 toaccommodate the increased distance' required between the lower end ofthe plunger II and the work contacted, the gauging device is adapted forchecking threads or work pieces of round form. In its inoperativeposition the arm 49 extends out of the way just below the wall 44 of thehousing, with the lower projecting portion of the arm extendingdownwardly at a considerable distance remote from the plunger and thepart of the housing on which this plunger is carried.

While the form of apparatus herein described constitutes a preferredembodiment of the inwention, it is to be understood that the inventionis not limited to this precise form of apparatus;

member movable in said support, gauging mechanism carried by saidsupport and operated by said gauging member, said support having aportion for holding a work specimen, an arm extending adjacent thegauging member, a plunger mounted for axial movement in said arm in linewith said gauging member and having one end engaging said gauging memberand the other end adapted for engagement with the work, a spring forurging said plunger yieldin'gly away from thegaugingmember, and meanspivotallymounting said arm on'said support for movement about an axisextending transversely of the axis of said plunger and providing forready withdrawal of the plunger from alignment with the gauging memberto provide for engagement of said gauging member with the work.

2. A gauging device a: the character described comprising a support, agauging member vertically movable in said support, gauging mechanismcarried by saidsupport and operated by said gauging member, said supporthaving a portion below said gauging member for holding a work specimen,an armpivoted for movement on a horizontal axis on said support andhaving a portion extending below said gauging member in the operativeposition of said am, a plunger mounted forvertical .movement. in saidarm in line with and below said gauging member and having its upper endengaging said gauging memmember.

. H. MARKWICK.

with the work, said arm being pivotally movable

